Abstract: This study aimed to examine how principals’ communication influences teachers’ self-efficacy in public secondary schools in Westlands Constituency- Nairobi County, Kenya. The study is anchored on Maslow’s Theory of Motivation. Mixed method approach with a concurrent mixed design was used. The target population was 14 public secondary schools, 14 principals, 14 deputy principals, and 322 teachers. Stratified proportionate and simple random sampling was used to select schools and teachers while purposive sampling was used for principals and deputy principals. The researcher sampled 5 schools, 5 principals, 5 deputy principals, and 98 teachers. Questionnaires and in-depth interviews guide were used for data collection. The validity and reliability of the quantitative instrument was established using Cronbach’s alpha to ascertain the internal consistency. Quantitative data was analysed using descriptive and inferential statistics and results presented using tables. The qualitative data were thematically analysed. Spearman rho was used to establish the relationships between variables as well as test the null hypothesis. The researcher ensured ethics throughout the process. The study established that principals’ leadership practices of communication significantly and positively influence teachers’ self-efficacy in public secondary schools. Communication demonstrated the strongest effect (rho = +0.719, p < 0.05), highlighting the core role of supportive dialogue in enhancing teacher confidence, competence, and effectiveness. This study recommends that the Ministry of Education should develop policies and targeted training programmes that equip school leaders with skills in effective communication and motivation and that the Ministry and relevant education authorities should develop policies that institutionalize continuous professional development for teachers. 

Keywords: Principals’ Leadership, Communication, Competence, Effectiveness, Motivation and Professional Development